mtd: hyperbus: rpc-if: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/linux-mtd/20231008200143.196369-11-u.kleine-koenig@pengutronix.de

memory: renesas-rpc-if: Remove Runtime PM wrappers

Now the rpcif_{en,dis}able_rpm() wrappers just take a pointer to a
device structure, there is no point in keeping them. Remove them, and
update the callers to call Runtime PM directly.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/d87aa5d7e4a39b18f7e2e0649fee0a45b45d371f.1669213027.git.geert+renesas@glider.be
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

memory: renesas-rpc-if: Pass device instead of rpcif to rpcif_*()

Most rpcif_*() API functions do not need access to any other fields in
the rpcif structure than the device pointer. Simplify dependencies by
passing the device pointer instead.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/0460fe82ba348cedec7a9a75a8eff762c50e817b.1669213027.git.geert+renesas@glider.be
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

mtd: hyperbus: rpc-if: Fix RPM imbalance in probe error path

If rpcif_hw_init() fails, Runtime PM is left enabled.

Fixes: b04cc0d912eb80d3 ("memory: renesas-rpc-if: Add support for RZ/G2L")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/f3070e1af480cb252ae183d479a593dbbf947685.1655457790.git.geert+renesas@glider.be

mtd: hyperbus: Make hyperbus_unregister_device() return void

The only thing that could theoretically fail in that function is
mtd_device_unregister(). However it's not supposed to fail and when
used correctly it doesn't. So wail loudly if it does anyhow.

This matches how other drivers (e.g. nand/raw/nandsim.c) use
mtd_device_unregister().

This is a preparation for making platform remove callbacks return void.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20220603210758.148493-2-u.kleine-koenig@pengutronix.de

mtd: hyperbus: rpc-if: fix bug in rpcif_hb_remove

The following KASAN BUG is observed when testing the rpc-if driver on
rcar-gen3:

root@rcar-gen3:~# modprobe -r rpc-if
[ 101.930146] ==================================================================
[ 101.937408] BUG: KASAN: slab-out-of-bounds in __lock_acquire+0x518/0x25d0
[ 101.944240] Read of size 8 at addr ffff0004c5be2750 by task modprobe/664
[ 101.950959]
[ 101.952466] CPU: 2 PID: 664 Comm: modprobe Not tainted 5.14.0-rc1-00342-g1a1464d7aa31 #1
[ 101.960578] Hardware name: Renesas H3ULCB board based on r8a77951 (DT)
[ 101.967120] Call trace:
[ 101.969580] dump_backtrace+0x0/0x2c0
[ 101.973275] show_stack+0x1c/0x30
[ 101.976616] dump_stack_lvl+0x9c/0xd8
[ 101.980301] print_address_description.constprop.0+0x74/0x2b8
[ 101.986071] kasan_report+0x1f4/0x26c
[ 101.989757] __asan_load8+0x98/0xd4
[ 101.993266] __lock_acquire+0x518/0x25d0
[ 101.997215] lock_acquire.part.0+0x18c/0x360
[ 102.001506] lock_acquire+0x74/0x90
[ 102.005013] _raw_spin_lock_irq+0x98/0x130
[ 102.009131] __pm_runtime_disable+0x30/0x210
[ 102.013427] rpcif_hb_remove+0x5c/0x70 [rpc_if]
[ 102.018001] platform_remove+0x40/0x80
[ 102.021771] __device_release_driver+0x234/0x350
[ 102.026412] driver_detach+0x158/0x20c
[ 102.030179] bus_remove_driver+0xa0/0x140
[ 102.034212] driver_unregister+0x48/0x80
[ 102.038153] platform_driver_unregister+0x18/0x24
[ 102.042879] rpcif_platform_driver_exit+0x1c/0x34 [rpc_if]
[ 102.048400] __arm64_sys_delete_module+0x210/0x310
[ 102.053212] invoke_syscall+0x60/0x190
[ 102.056986] el0_svc_common+0x12c/0x144
[ 102.060844] do_el0_svc+0x88/0xac
[ 102.064181] el0_svc+0x24/0x3c
[ 102.067257] el0t_64_sync_handler+0x1a8/0x1b0
[ 102.071634] el0t_64_sync+0x198/0x19c
[ 102.075315]
[ 102.076815] Allocated by task 628:
[ 102.080781]
[ 102.082280] Last potentially related work creation:
[ 102.087524]
[ 102.089022] The buggy address belongs to the object at ffff0004c5be2000
[ 102.089022] which belongs to the cache kmalloc-2k of size 2048
[ 102.101555] The buggy address is located 1872 bytes inside of
[ 102.101555] 2048-byte region [ffff0004c5be2000, ffff0004c5be2800)
[ 102.113486] The buggy address belongs to the page:
[ 102.118409]
[ 102.119908] Memory state around the buggy address:
[ 102.124711] ffff0004c5be2600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 102.131947] ffff0004c5be2680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 102.139181] >ffff0004c5be2700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 102.146412] ^
[ 102.152257] ffff0004c5be2780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 102.159491] ffff0004c5be2800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 102.166723] ==================================================================

The above bug is caused by use of the wrong pointer in the
rpcif_disable_rpm() call. Fix the bug by using the correct pointer.

Fixes: 5de15b610f78 ("mtd: hyperbus: add Renesas RPC-IF driver")
Signed-off-by: George G. Davis <davis.george@siemens.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20210716204935.25859-1-george_davis@mentor.com

mtd: hyperbus: rpc-if: Check return value of rpcif_sw_init()

rpcif_sw_init() can fail so make sure we check the return value
of it and on error exit rpcif_hb_probe() callback with error code.

Fixes: 5de15b610f78 ("mtd: hyperbus: add Renesas RPC-IF driver")
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20211025205631.21151-5-prabhakar.mahadev-lad.rj@bp.renesas.com

memory: renesas-rpc-if: Add support for RZ/G2L

SPI Multi I/O Bus Controller on RZ/G2L SoC is almost identical to
the RPC-IF interface found on R-Car Gen3 SoC's.

This patch adds a new compatible string for the RZ/G2L family so
that the timing values on RZ/G2L can be adjusted.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20211025205631.21151-8-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>

mtd: hyperbus: add Renesas RPC-IF driver

Add the HyperFLash driver for the Renesas RPC-IF. It's the "front end"
driver using the "back end" APIs in the main driver to talk to the real
hardware.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/78abb851-2beb-fe7d-87e5-ce58ee877d35@gmail.com